Choose one that suits your home and saves you money.
Choosing the best air conditioner can be a challenge. What size do you need? How much will it cost to run and how noisy will it be? We'll help you find the right model for your home.
This guide focuses on split-systems, as these are the most popular type of air conditioner in Australia. You can also check out our ducted air conditioner buying guide, and our portable air conditioner buying guide.
On this page:
What type of air conditioner should I get?
Reverse-cycle vs cooling only
What size air conditioner do I need?
How much does it cost to run an air conditioner?
How noisy are air conditioners?
Features to consider
Air purifying filters
When is the best time to buy an air conditioner?
How to install a split-system air conditioner
Buy smarter with CHOICE membership
Find the best brands
Avoid poor performers
Get help when things go wrong
What type of air conditioner should I get?
For most homes, a reverse-cycle split-system air conditioner will be the best option. Let's break down what that means.
Types of air conditioners and their costs
Split-system
These have two parts: an indoor unit and an outdoor unit, connected by pipes containing refrigerant gas. They are the most common air conditioner type in Australia, and are good for a room or open plan area up to about 60m2.
Price range: $600–5500.
Multi-split
Similar to a split-system, but with one outdoor unit connected to two or more indoor units. Good for two or three rooms that are reasonably close together, especially when separate split-systems or a ducted system aren't suitable.
Price range: About the same price range as the equivalent separate split-systems ($600–5500 per system).
Ducted
These have a discreet central unit, usually located out of sight in your roof, connected by air ducts to air outlets and sensors in each room. Good for cooling and heating a whole house. See our ducted air conditioner buying guide for more details.
Price range: $5000+ (can easily be $10,000 or more).
Wall/window
A single box unit, installed in a window or through an external wall. Good for rooms and open-plan areas of up to 50m2. Smaller units can be plugged into a normal power point; larger ones may need additional wiring. Not quite as efficient or effective as split-systems but a reasonable budget option if a split-system isn't an option (for example if you're renting).
Price range: $400–1100.
Portable
A single unit that can be moved from room to room as needed (but generally not easily). Most have a flexible duct that must be attached to a window to vent the heat outside. Good for rooms in households when a built-in option isn't feasible (such as if you're renting). Not as efficient as split-systems. See our portable air conditioner reviews.
Price range: $300–1300.
CHOICE tip: You don't need to pay top dollar to get the best air conditioner. Some recommended models in our air conditioner reviews cost under $1500.
Rooms and open-plan areas of up to 50 square metres. Usually installed in a window or external wall. Smaller units can be plugged into a normal power point; larger ones may need additional wiring. Not very common. Price range: $400–$1100.
Looking for air conditioners? We've tested to find you the best. See air conditioners review
Reverse-cycle vs cooling only
A reverse-cycle air conditioner can heat as well as cool – in fact, it's one of the cheapest ways to heat your home in winter.
In cooling mode, a split-system air conditioner extracts heat from the indoor air and moves it outside, via the refrigerant gas in the pipes connecting the indoor and outdoor units. The outdoor unit releases the heat and pumps the cooled refrigerant back to the indoor unit where the cycle continues. In heating mode, the process is simply reversed, to extract heat energy from the outdoor air and send it indoors (yes, even in cold weather there's some heat energy in the outdoor air).
If you only need an air conditioner for cooling in summer (for instance, if you live in an area with mild winters or you already have another heating system), then a cooling-only air conditioner could be right for you. They're generally cheaper than reverse-cycle models but usually have all the same features.
Our review contains both reverse-cycle and cooling-only models.
In terms of cooling efficiency and running costs, there isn't a big difference between most cooling-only and reverse-cycle models, but in our review, the most efficient models for cooling are actually reverse-cycle. Perhaps because reverse-cycle is the most popular type of air conditioner, the market for them is more competitive and it may be that manufacturers invest more in developing efficient reverse-cycle models.
So, even if you only use heating occasionally, you're better off getting a reverse-cycle model in most cases. But if you only ever need your air conditioner to cool you down, then a cooling-only model is definitely worth considering.
Read more: How we test air conditioners
What size air conditioner do I need?
Here's our rough guide to the air conditioner capacity (size) you'll need for a particular room size (in square metres).
Read the full article 'What size air conditioner do I need?'.
Room sizeCapacityUp to 20 sq m2–2.5kW20–40 sq m2.5–5kW40–60 sq m4–6kW60–80 sq m5–7kW80+ sq m6–9kW
So, that's the ballpark guide, but you really need to do an accurate calculation before buying your air con, or else you'll run into these issues:
Models that are too powerful for the room size may run frequent short cycles to achieve the target temperature. This can result in the room getting too cold or hot, inadequate dehumidification (i.e. not drying the air enough, making the room feel less comfortable), increased power consumption and running costs, and wear and tear on the system.
Underpowered models may have to run more often at maximum output, which could dry the air too much and also create excessive wear.
CHOICE tip: Choose a model with equal or slightly greater capacity for the room.
For example, if you calculate the room needs a 6kW model, then look for an air conditioner with rated cooling capacity in the range 6kW to 6.5kW (roughly). It's probably a safer bet to get a model slightly above the required capacity than slightly below it, as a little extra grunt may help in extreme temperatures. But don't go too much above the required capacity.
How to do a proper calculation
Some installers and online calculators offer only a simplistic analysis and may tend to recommend a larger capacity than you really need.
But there are a lot of variables to consider. For example, a well-insulated room with south-facing windows will be at the bottom end of the capacity range, while an uninsulated room with west-facing windows will be towards the top.
Likewise, a room in Perth will probably need a more powerful air conditioner compared to an otherwise identical room in Sydney.
A proper calculation takes all the room's details into account:
The size of the room: length, width and height.
The type of room: living room, open-plan living room and kitchen, bedroom, etc.
The size and orientation of the windows and glass doors. A large north- or west-facing window can let in a lot of heat in summer.
Shading and curtains on the windows.
Insulation of the floor, ceiling, and walls.
The local climate.
The cooling load and heating load calculators on fairair.com.au, by the Australian Institute of Refrigeration, Air Conditioning and Heating (AIRAH), are worth using – they allow you to factor in a lot of details about the room, its insulation, window orientation and more to get an accurate guide to the right air conditioner size. Omnicalculator.com also has a size calculator you can try. Alternatively you can try the calculators on manufacturer and installer websites, but we think these tend to overestimate the capacity you need.
Read more: Top 10 tips to keep your home cool
How much does it cost to run an air conditioner?
Running costs for a medium-sized air conditioner ranges from around $400–550 a year.
We measure running costs in our air conditioner reviews. As you can see in the below table, running costs can vary by a few hundred dollars a year, depending on the model.
Running costs of air conditioners we testedSizeApproximate yearly cost to run*Small (up to 4kW)$310–490Medium (4–6kW)$390–550Large (over 6kW)$420–600* Based on how much each model costs to deliver a set amount of cooling and heating per year at maximum capacity, with the remainder of the year in standby mode (based on electricity costs of 30 cents/kWh). It's only indicative – your actual running costs may vary.
How to save money when running your air conditioner
What's the ideal air conditioner temperature for electricity savings?
Does an inverter air conditioner save money?
Solar powered air conditioners
Read more: Air conditioner energy saving tips
How noisy are air conditioners?
Most modern split-system air conditioners are very quiet indoors and out, but it's worth checking an air conditioner's noise levels before you buy.
We measure noise as part of our split-system air conditioner reviews. In our latest test, the noise from indoor units ranged from 19dB to 53dB, and from the outdoor units, 42dB to 69dB (measured on the quietest indoor fan setting).
For comparison, here are some common sound levels:
30dBA: typical sound level of a quiet home
50dBA: interior of a quiet car while driving
60dBA: typical conversation
70–80dBA: vacuum cleaner
A noisy indoor unit may interfere with your activities, conversation or sleep. A noisy outdoor unit can disturb you (if it's too close to a bedroom or living room window) or your neighbours, so consider outdoor unit placement carefully.
Most local councils have noise restrictions relating to the use of air conditioners. Check council regulations before buying, and your strata rules if you live in an apartment, especially if the outdoor unit needs to be installed close to a neighbour's house.
Features to consider
Looking for portable air conditioners? We've tested to find you the best. See portable air conditioners review
Fan speeds
The fan circulates cooled or heated air around the room. Look for a model with a wide airflow range and multiple fan speeds: from very high – to help the room cool down quickly, to very low – so there's less noise and no unpleasant draught once you have the right temperature.
Operating modes
Auto: Automatically chooses the mode required to keep the room at the chosen temperature.
Cool: Pumps heat from the inside to the outside, cooling the room.
Heat: Pumps heat from the outside to the inside, warming the room.
Dry: Dehumidifies the air. Provides some cooling, but not as much as cooling mode.
Fan only: Blows air without heating, cooling or drying, which is useful when all you want is a cooling breeze.
Economy: Also called Eco mode, this reduces power consumption. Different brands implement this in different ways. It may simply reduce the cooling or heating output by adjusting the thermostat a degree or two, or it may use sensors to detect if no one is in the room and then reduce the cooling/heating.
Human presence sensor
This detects whether someone is in the room, so the unit knows to keep working. Some models even direct the air movement towards the sensed person. When no one is detected, the unit might switch to an economy mode to reduce power consumption.
Having this feature doesn't mean you can leave the air conditioner running for hours when the house is empty. You're still much better off turning it off and using the timer function to turn it back on just before you return home, or turning it on remotely via Wi-Fi (see next item).
This feature goes by different names. Mitsubishi Electric calls it Absence Detection; for Mitsubishi Heavy Industries, it's Eco Operation; for Panasonic it's ECONAVI; for Daikin, it's Intelligent Eye.
Many newer-model air conditioners can be controlled remotely via an app on your smartphone.
Wi-Fi and apps control
Many newer models can connect to the wireless network in your home so you can control the air conditioner via an app on your smartphone – handy if you're at work and want to turn it on before you get home, or you're at home and you've misplaced the remote.
Some have this feature built in, while others need a controller device added to the air conditioner to enable it.
Remote control
Look for large, well-spaced buttons with easy-to-read labels, and a big, easy-to-read LCD screen.
Read more: How to clean your air conditioner
Air purifying filters
All air conditioners have a dust filter in the indoor unit. This traps dust from the air as it circulates through, mainly to stop it clogging up the internal workings. But the dust filter will only have a minimal effect, if any, on smoke and other very fine particles.
To filter out smoke, you really need a HEPA filter. But HEPA filters can't practically be fitted to split-system or ducted air conditioners, because air conditioners have to deliver quite significant volumes of air flow into the room, and would need massively powerful fans in the indoor unit to force that amount of air through the very tight weave of a HEPA filter.
However, many new air conditioner models do have an air purification feature, typically based on ionisation or photocatalytic filters, This is not likely to be as effective as the HEPA filter that you'd find in a dedicated air purifier, but could still be useful in removing some dust, smoke, mould spores and even viruses and bacteria from your indoor air.
Our guide to air conditioner air purifier filters explains the details of how these filters work.
Online, you may find various aftermarket air purifying filters for air conditioners, described as electrostatic, activated carbon or similar. They claim to be compatible with major air conditioner brands and in some cases can be cut to size to suit different models. Be cautious with any such filters. While they may provide filtration as claimed, it's highly unlikely that they've been thoroughly tested with every air conditioner brand, and using non-genuine parts may reduce your air conditioner's performance, possibly cause damage and could void your warranty.
The remote control should be easy to read and use with well-spaced buttons.
Sleep mode
This function adjusts the temperature in steps to a comfortable level for sleeping so the air conditioner doesn't work as hard (and is quieter) when you're sleeping.
Adjustable or oscillating louvres
We recommend you point them up for cool air and down for warm. This can be done via the remote for most models. Left and right adjustability helps direct air to where it's needed.
Restart delay
Protects the compressor by preventing the air conditioner from starting up again too soon after being switched off.
Demand Response Enabling Device (DRED)
If you have an air conditioner with the Demand Response Enabling Device (DRED, or PeakSmart) feature, and your energy provider offers the PeakSmart service, they'll be able to remotely switch your air conditioner to an economy mode during times of high demand on the grid.
This will usually have no major impact on the air conditioner's cooling (or heating) output – you might not even notice it happening – but it will reduce the amount of power the air conditioner is using, not just saving you money but also reducing the need for more 'poles and wires' to meet energy needs.
So far only a few energy companies provide the service. Some energy companies, including Queensland-based Energex and Ergon, also pay incentives to customers who buy DRED-enabled air conditioners.
A high-wall mounted air con will blow air easily across a room.
Wall-mounted or ceiling-mounted?
High wall: the indoor unit is mounted high on a wall so its air flow can easily blow across the room.
Floor-mounted: the indoor unit is at floor level, which may be better suit some rooms.
Cassette: the indoor unit is mounted in the ceiling.
Floor/ceiling: can be mounted on either the ceiling or the floor.
Operating range
Do you live in a very hot or cold region? Most models can operate in temperatures from about -10°C up to about 45°C or more. This is sufficient for most parts of Australia, but check the air conditioner's operating range before you buy, to make sure it can cope with any extremes in your area. (If you live in a hot and dry climate, an evaporative cooler can be a cheaper alternative to an air conditioner.)
Automatic de-icing
If you live in a cold area, get an air conditioner with automatic de-icing to avoid frost building up on the outdoor heat exchanger coils in winter.
Refrigerant gas
Ozone-depleting refrigerants such as chlorofluorocarbons (CFCs) have been essentially phased out, but the most commonly used current refrigerant gas type, hydrofluorocarbon or HFC, is also problematic. In 2016 a new international agreement was reached to phase out the use of HFCs over the next few decades.
We're seeing a clear trend in the models we test towards the use of R32, instead of R410A. These are both HFCs, but R32 has a lower global warming potential and should also give improved efficiency.
When is the best time to buy an air conditioner?
Avoid buying in peak season if you can – that will be summer in most parts of Australia, but could be mid-winter too if you're in a colder region. Installers are usually very busy in these periods and you might have to wait some weeks before your new unit can be installed.
If possible, shop around before the peak season starts, so that your new unit is installed and ready for when you'll need it most.
Alternatively, it can be worth buying just after the season ends. Old stock may be discounted as retailers make room for new models.
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